Author/Authors :
DAGDELEN, Fethi Fırat Üniversitesi - Fen Fakültesi - Fizik Bölümü, Turkey , BUYTOZ, Soner Fırat Üniversitesi - Teknoloji Fakültesi - Metalurji ve Malzeme Mühendisliği, Turkey , KOK, Mediha Fırat Üniversitesi - Teknoloji Fakültesi - Metalurji ve Malzeme Mühendisliği, Turkey , ERCAN, Ercan Bitlis Eren Üniversitesi - Fen Edebiyat Fakültesi - Fizik Bölümü, Turkey
Title Of Article :
Heat treatment effects on thermal cycle, transition temperature and microstructure of NiTi SMA
Abstract :
The thermal stability (cycle) and activation energies of NiTi shape memory alloy (SMA), in Ni-45.16%Ti atomic concentration exposed to heat treatment in air in the temperature range 400-800 °C, was investigated. The thermal cycles tend to low transformation temperature, and couldn’t display R phase. Experimental results indicate that thermal stability of as-cast and heat treated samples were decreased. The thermal activation energies of these alloys were determined by Differential Scanning Calorimeter (DSC). It was seen that both transformation temperature of samples (Ms, Mf, As and Af) and the thermal activation energies calculated by Ozowa and Kissinger methods increased with the heat treatment. However, it was determined that Vickers hardness values of these shape memory alloys were decreased with the heat treatment.
NaturalLanguageKeyword :
NiTi , shape memory alloy , thermal cycle , heat treatment
JournalTitle :
Erciyes University Journal Of The Institute Of Science and Technology
